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Bees play a crucial role as natural pollinators, ensuring the maintenance and stability of the world's biodiversity and agricultural crops. Native bees in neotropical regions belong to the Meliponini tribe, a larger group that differs significantly in behavior and biology from honeybees (e.g., Apis mellifera) and solitary bees (e.g., Osmia spp.). Hence, the exposure and effects of pesticides is also likely to vary among these different species. The aim of this study was to develop an analytical method to determine the presence of the neonicotinoid clothianidin in the Brazilian native stingless bee Tetragonisca angustula (local common name: Jataí). The method used for the chemical analysis involved a QuEChERS technique combined with UHPLC-MS/MS analysis. The developed method was subsequently used to analyze collected field samples. In addition, the acute toxicity of the pesticide to T. angustula was evaluated in a laboratory bioassay evaluating both lethal and sublethal endpoints. The analytical method was successfully developed with detection and quantification limits of 1.55 and 5 μg L−1, respectively, along with a linear range of 1–5 ng mL−1. Clothianidin was detected in environmental samples (9.2–32.9 ng g−1), and the exposure experiments demonstrated acute oral toxicity to adults of T. angustula , (24 h-LD 50 of 0.16 ng a.i./bee), as well as no significative interference in acetylcholinesterase activity. Considering the obtained toxicity endpoints for T. angustula and those reported in the literature for other bee species, this study revealed that T. angustula is more (lethally) sensitive to clothianidin than other bee species, including those commonly used in environmental risk assessment studies. This thus also supports the call for using native test species in (regional) risk assessment evaluations. [Display omitted] • Optimized and validated method for the determination of clothianidin in native bees. • Determination of the oral susceptibility of Tetragonisca angustula to clothianidin. • Quantification of the lethal concentration doses of clothianidin in native bees. [ABSTRACT FROM AUTHOR]

The laser ablation sector field inductively coupled plasma mass spectrometry (LA–SF–ICP-MS) U–Pb geochronological method is frequently used to date minerals, in particular zircon. In turn, baddeleyite is the ideal geochronometer when it comes to silica-undersaturated rocks, such as alkaline rock types. In this study, we describe a series of protocols to separate baddeleyite crystals and date them by the LA–SF–ICP-MS method in the Isotopic Geology Laboratory of the Geoscience Institute (University of Campinas), starting from sample crushing and milling and the calibration of the Wilfley table. The method includes the use of Kovdor and Phalaborwa primary and secondary reference materials, respectively. Laser operation conditions were spot size of 25 μm and ablation time of 60 s (20 for local blank and 40 for baddeleyite signal), at a fluence of 20 L per minute. Cretaceous alkaline rocks associated with the Paraná-Etendeka magmatic province were analyzed, comprising Jacupiranga, Pariquera-Açu, and Cananéia intrusions, all related to the Guapiara lineament. The results yielded concordant baddeleyite ages of 115–120 Ma for Jacupiranga carbonatite, around 110 Ma for Pariquera-Açu shonkinite, and 81 ± 2 Ma and 83 ± 0.4, respectively for baddeleyite and zircon from the Cananéia syenite. Despite the difficulties in baddeleyite separation, the LA–SF–ICP-MS U–Pb ages have proven to be robust for the young alkaline complexes related to the Serra do Mar Province, such as those occurring along the São Jerônimo-Curiuva Lineament, avoiding the concerns about thermal events that could reset, e.g. K–Ar and Ar–Ar systems. Field relations show a hierarchy of intrusive pulses and our data show that, temporarily, the Jacupiranga Complex is active in a younger time interval, 115 to 120 Ma, than previously established. • U–Pb baddeleyite crystallization ages of Jacupiranga Complex. • Cretaceous alkaline carbonatite of Jacupiranga Complex. • U–Pb baddeleyite and zircon crystallization ages of alkaline rocks from south of São Paulo state, Brazil. [ABSTRACT FROM AUTHOR]

Metal coordination complexes are chemotherapeutic and anti-inflammatory agents. The ruthenium complex FOR811A ([Ru(bpy) 2 (2-MIM)Cl](PF 6) 3) FOR811A was evaluated in mice models of acute inflammation and behavioral tests. Animals received FOR811A (3, 10 or 30 mg/kg; i.p.), indomethacin (20 mg/kg; i.p.), L-NAME (20 mg/kg; i.v.) aminoguanidine (50 mg/kg; i.p.) or dexamethasone (0.5 mg/kg; s.c.) 30 min before inflammatory stimulation. Paw edema was induced by carrageenan (400 μg/paw), TNF-α or L-arginine (15 nmol/paw) (5 ng/paw) and evaluated by hydropletismometry 4 h later. Peritonitis was induced by carrageenan (500 μg; i.p.) and evaluated 4 h later for hypernociception and quantification of total/differential leukocytes, total protein reduced glutathione (GSH) and myeloperoxidase (MPO). FOR811A inhibited the paw edema induced by carrageenan at 3 (64%; p < 0.0001), 10 (73%; p < 0.0001) and 30 mg/kg (66%; p < 0.0001), and at 10 mg/kg that induced with L-arginine by 75% or TNF-α by 55% (p = 0.0012). Paw tissues histological analysis showed reduction in mast cells (46%; p = 0.0027), leukocyte infiltrate (66%; p < 0.0001), edema and hemorrhagic areas. Immunohistochemical evaluation revealed inhibition of iNOS (62%; p < 0.0001) and TNF-α (35%; p < 0.0001). In the peritonitis model FOR811A increased (2.8X; p < 0.0001) hypernociceptive threshold, reduced total leukocytes (29%; p < 0.0001), neutrophils (47%; p = 0.0003) and total proteins (36%; p = 0.0082). FOR811A also inhibited MPO (47%; p = 0.0296) and increased GSH (1.8X; p < 0.0001). In the behavioral tests, FOR811A reduced (30.6%) the number of crossings in the open field, and increased (16%) the number of falls in the Rota rod. Concluding, FOR811A presents anti-inflammatory and antioxidant effects, via nitric oxide pathway. • FOR811A is a ruthenium coordination complex presenting antiinflammatory action. • FOR811A inhibits mice acute inflammation involving TNFα and NO. • FOR811A inhibits acute inflammation via modulation of iNOS. [ABSTRACT FROM AUTHOR]

• F/I ratio influences the degradation of lignocellulosic biomass constituents. • F/I ratio of 0.5 led to the lowest VFAs accumulation in during all co-digestions. • SS-AD co-digestion of poultry manure and corn cob led to highest methane yields. • Thermal energy produced with CC-PM replaced half the energy spent with firewood. • Groot's multi-stage model best fitted the methane production data. Six typical Brazilian lignocellulosic biomasses (rice straw, corn cob, peanut shell, sawdust, coffee husk and sugarcane bagasse) were evaluated for methane production by solid-state anaerobic co-digestion with poultry manure. The results showed the highest methane production was obtained with corn cob and poultry manure (126.02 Nm3 CH 4. ton residue−1) using a food to inoculum ratio of 0.5, which lowered volatile fatty acids accumulation. In this condition, the thermal energy production (1.73 MJ.kg live chicken−1) would be able to replace 53.2% of the energy with firewood in poultry farming. The high hemicellulose and low lignin content in corn cob seem to explain the biomethanation of such biomass, and this agrees with the microbial analysis which revealed the predominance of bacteria related to plant polysaccharides hydrolysis and carbohydrate conversion in the inoculum. The methane production was best modelled by Groot's multi-stage model, and the microbial adaptation to lignin might explain this. [ABSTRACT FROM AUTHOR]

Lectins represent a class of proteins or glycoproteins capable of reversibly binding to carbohydrates. Seed lectins from the Dalbergieae tribe (Leguminosae) have structural variability, carbohydrate specificity, and biological effects, such as inflammation, vasorelaxation and cancer antigen binding. To comprehensively address these factors, the present work aimed to establish and characterize the three-dimensional structure of Centrolobium microchaete lectin (CML) by homology modeling, investigate protein-carbohydrate interactions and evaluate its inflammatory effect on mice. Molecular docking was performed to analyze interactions of the lectin with monosaccharides, disaccharides and N- glycans. Two dimannosides, methyl mannose-1,3-α-D-mannose (MDM) and mannose-1,3-α-D-mannose (M13), were used in molecular dynamics (MD) simulations to study the behavior of the carbohydrate-recognition domain (CRD) over time. Results showed an expanded domain within which hydrophobic interactions with the methyl group in the MDM molecule were established, thus revealing novel interactions for mannose-specific Dalbergieae lectins. To examine its biological activities, CML was purified in a single step by affinity chromatography on Sepharose-mannose matrix. The lectin demonstrated inflammatory response in the paw edema model and stimulated leukocyte migration to the animal peritoneal cavities, an effect elicited by CRD. For the first time, this work reports the molecular dynamics of a lectin from the Dalbergieae tribe. [ABSTRACT FROM AUTHOR]